If we assume that a biological sample measurement device for measuring blood glucose levels is used in a hospital, for example, where there are many operators and many patients, the operators and the patients using the device need to be identified. Therefore, ID's must be assigned to the operators and patients, and inputted into the device.
For inputting information in the past, an information terminal device was provided with a display component and a plurality of character keys indicating characters or numbers arranged in an array beneath the display component (see Patent Literature 1 below, for example).